Rules Governing the Use of the S5-115F
S5-115F Manual
Number and location
Only one interrupt DI can be used in each subunit.
The interrupt DIs must be plugged into the central controller.
Their addresses cannot be used for any other modules, including DQ modules.
Process interrupt OB 2
Make sure that OB 2 is correctly executed in the case of process interrupts.
Synchronization FB 254
To service process and time interrupts with the required speed, you must synchronize the control
program sufficiently often. For this purpose, you must call synchronization FB 254 with the
appropriate parameters ( Vol. 2, 6.1.6 of the Manual).
The 115F operating system monitors the maximum intercall interval you have configured with
COM 115F ( Vol. 2, 1.1.1 of the Manual).
Process interrupt response time
The time taken to respond to a process interrupt depends on the intervals between the FB 254 calls
in the user program. The response time corresponds to the interval between the calls plus a
maximum of 10 msec. operating system processing time. The minimum response time is 30 msec.
User program without process or time interrupt
Note
If you do not handle any process or time interrupts in the user program, you can
shorten the PLC scan time by using the IA ”inhibit alarm (interrupt)” operation.
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EWA 4NEB 811 6148-02